Lain is a distinctive boys' name in United States, ranking #4706 in 2004 with 18 recorded births. The name reached its all-time peak in 2011 with 25 births ranking #4053. Since 1996, the popularity has increased by 63.6%. In 2004, approximately 1 in every 110,267 boys born was named Lain. RISING Recent data shows the name is currently rising.